[chimico]

Hi, i haven't understand that chapter of my book and i've some questions:

1)Why to balance the repulsion of protons in nucleus are necessary the neutrons, if they have no electric charge?
2)What are the alpha particles and what they are in common with He²⁺?
3)What are the beta particles ?
4)How is it possible that a neutron become a proton?
5)How the tritium became He + e ? and why C¹⁴ became N + beta ?
i don't understand how it's possible that an element is transformed in another element different and where are from the alpha and beta particles?


Thank and sorry my english!

[Fluorine]

1) Neutrons determine a element's isotope. Isotopes posses unique characteristics compared to others of the same element. Even though neutrons have no charge they help space out protons, preventing them from repelling each other and splitting up the nucleus. They use strong force to bind together and with protons.

2) An alpha particle is two protons and two neutrons. Now think about how this compares to helium or ionized He²⁺, as you said.

3) Beta particle

4) Beta decay

5) Take a look at these; tritium decay and ¹⁴C decay

[chimico]

so if I add or sub electron, neutron and proton in an element, is possible to transform it in another fully different?
for example N to O, Ca to K and etc..?
seem a bit strange..

How it's possible to add a neutron to plutonium? just shot it in the nucleus or need some other operation?

is real that the ALL pure elements are composed by isotope ?
in my book i read that Cl is composed by Cl-35 and Cl-37 but all elements are a mix of isotope?
what is the procedure to know what isotope are present?


Thank!

[Fluorine]

so if I add or sub electron, neutron and proton in an element, is possible to transform it in another fully different?

If you simply add/subtract then no, only protons will change the element, neutrons will form isotopes, and electrons will form ions of the same element.

How it's possible to add a neutron to plutonium? just shot it in the nucleus or need some other operation?

is real that the ALL pure elements are composed by isotope ?
in my book i read that Cl is composed by Cl-35 and Cl-37 but all elements are a mix of isotope?

Yes, every element has it's own isotopes. In some cases there is one major isotope and a few minor by occurrence in nature. See this table for a visual.

what is the procedure to know what isotope are present?

Isotope vary in mass so they can be separated with sensitive equipment.

Check these out;
http://en.wikipedia.org/wiki/Isotope_separation
http://en.wikipedia.org/wiki/Isotope_ratio_mass_spectrometry

[vmelkon]

Yes, you shoot a neutron at a sample of plutonium and the neutron might bind to the nucleus of Pu.

Most elements have several stable isotopes such as hydrogen (hydrogen 1 and hydrogen 2 are stable).
Some elements have a lot of stable isotopes like tin.
Some elements only have 1 stable isotope such as aluminum (aluminum is 100% Al 27, gold is 100% Au 197, iodine is 100% I 127).

[chimico]

why do only proton change an element's property if every one have a different number of electron too?

By what machine a proton is shooted to nucleus?


Thanks!

[vmelkon]

Which property are you talking about?
Anyway, chemical properties of an elements come from the electronic configuration. It also comes from how many atoms are together, in a cluster as well. There was some research about a bunch of Ag atoms having similar properties as a single Platinum atom.

By what machine a proton is shooted to nucleus?

Cyclotron.
Linear accelerator. You can ionize some hydrogen and use these as a source of protons.

[chimico]

so changing the number of electron in an atom we could obtain hydrogen from nitrogen, for example?
why I never heard about that?

In my chemistry book i read every level is divided in sublevels, but what they are?

[rabolisk]

You have to change the number of protons to get a different element. Changing the number of electrons only results in ions.

[jeffrey.struss]

This is correct. You do not get new elements by changing electron number you DO get ions though which behave differently from each other. For exampel,Fe behaves differently than Fle(II) which behaves differently than Fe(III). So chemically they are different species but still the same element.

[vmelkon]

so changing the number of electron in an atom we could obtain hydrogen from nitrogen, for example?
why I never heard about that?

In my chemistry book i read every level is divided in sublevels, but what they are?

No, you don't get hydrogen.

As for orbitals, that requires pages of explanations
http://en.wikipedia.org/wiki/Atomic_orbital

[chimico]

if the electrons of a gas, for example, emit energy only when they go down level, then to get the atomic spectrum should I first give energy and then wait until electrons go down from their level?
is important how many energy I give?